let header_vm=new Vue({
    el:"header",
    data:{
        c_arr:[],
        user:""
    },
    created:function () {
        axios.get("/category/select").then (function (response) {
            //this代表当前的Vue对象header_vm
            header_vm.c_arr=response.data;

        })
        axios.get("/checkLogin").then(function (response) {
            header_vm.user=response.data;

        })

    }
})